Everytime i try to join server {FH}FFA it has this error message that says "Someones using this CD Key" what does that mean how do I fix this?

Hello there.
I have had the same issue several times and from my experience this happens when your connection crashes caused by computer, game, router, light cut, etc. and the "game" thinks you are still on.

Since the issue is from the "other end" there is not much one can do but wait. It usually only takes several minutes for it to reset.

Hope it helps

Cappy

Do you have a discord?